How to find bugs

Open your page with Chrome browser, press the Ctrl-Shift-I keys (if Mac, press the Option-Command-I) -> open the Resources panel -> drill down into the files folders(Images, Scripts or Stylesheets folder), then you will easily find if your page contains bugs. The Chrome browser will mark a red symbol besides a file name if the file contains bugs: …

I would suggest finding some tools to find out how the app is performing on different devices and screen sizes (resolution). Google’s Chrome has a tool in Inspect mode called “device toolbar” witch lets you emulate different devices and resolutions. There are many more other tools like this, some free and some a bit costly. …